Chuck for boring-machines, lathes, or the like.



J. W. BARNES) CHUCK FOR BORING MACHINES, LATHE-S, OR THE LIKE.

APPLICATION FILED JUNE 28, 1911. 1,1 12,348.

Patented Sept. 29, 1914.

' radial position of the keys and their 611-". gagement with side recesses formed in a colwithin the socket and 'Bn'mms, a subject of theKinlg spherically.

JOHN WILLIAM BARNES, OF ROCK FERRY, ENGLAND.

CHUCK Ion. nonma-nncnmns, Ll'rmts, on THE 'LIKE.

Specification of Let-ters Patent. Application filed June 26, 1am. serial no. cause.

To all whom it may concern v Be it known that I,'- Join; WILLIAM of Great Britain, and-a resident of Rock. erry, England, have invented certain new and useful Improvements in Chucks for Boring-Machines, Lathes, or the like, of which the fol: lowing is a specification.

This invention relates to improvements 1n chucks or similar appliances adapted for holding drills, borin bits, reamers, and the like in drilling mac ine's, boring machines, electric or pneumatic drills or turret boxes of lathes, and relates to an appliance such that the tool or drill ,may be readily en'- gage'd or disengaged and the connection of the drill or analogous tool with -'the chuck be of such a character that the tool may itself -with the float and consequently allne hole to be drilled or boredzf-g I According to this invention the appliance comprises a socket piece rovided with slots fitted with radially mova le keys the'socket piece being fitted with an outer sleeve slid-- able thereon and adapted to-control the let piece fittin which engages t e drill, boring bit, or the like. Further features of this invention consist in making the shank or adapter of the socket piece detachable therefrom by screwing or otherwise and in providing stops for the outer sleeve to limit it in its engaged and disengaged positions.

The invention is illustrated in the accompanying drawing in which,

Figure 1 is a longitudinal section through an adjustable chuck constructed in accordance with this invention. Fig. 2 is a view analogous to Fig. l in which the base of the collet and socket head are made hemi- In carryin out the invention, the shank or adapter 0 the socket piece is made detachable therefrom by screwin it into the head of the socket at 3 the a apter being provided with a flange 4, which, when the adapter is screwed into the socket piece, projects beyond the exterior of the latter and thus acts as a stop to the movement of the outer sleeve 5 in one direction, and trues the adapter with the socket when screwed home. 01' the spindle portion may be made as part of the socket having flanges screwed at the bottom or top end as may be reping out of; position.

Patented Sept. 29, 1914.

quired. This outer sleeve is provided with the'la'tter is in its upper or lower limiting I position;.- respectively. The spring controlled catches are so designed as to lightly engage with the grooves 10 but may be disengaged when desired by a sharp movement, an thus enable the chuck to be used hori- 'zont-a'lly or vertically without sleeve slipa'dapter shank 1 into the socket piece 2,

By screwing the s'hanks of varying sizes to suit different conditions may be inserted.

The segmental keys 11 engage the side recesses 12 formed in the col et piece 13 and .t-hus drive the drill 14 or the like which en-. -.gage's with its tang 15 in a slot 16 formed in the head of the collet piece. The seg mental keys 11 are retained in engagement by the position of the outer sleeve 5. To release the drill and collet piece from engagement with the socket 2, the sleeve 5 is moved to the position shown in the drawing, the segmental keys then flying out, by'centrifugal action, into the recesses 17 in the interior of the sleeve leavingthe collet piece 13 free to be withdrawn. 'When the collet piece and drill have been reinserted, the

outer sleeve. is slid back again, the inner beveled surface 17 forcing t gagement with the collet. The e es of the segmental locking keys 11 if left s arp and square are apt to bind against the inner beveled surfaces 17" of the outer sleeve 5. and to obviate this it is pro osed in this invention to round or bevel of? the upper corners of the keys as shown at 7 b so that an easier engaging action between the keys and the sleeve may-be obtained.

Such an arrangement of adjustable chuck has many advantages inasmuch as it enables the drill to absolutel aline itself and so drill a perfectly true ole. To achleve this it is desirable to make a slight clearance between the collet 13 and the socket 2 thus enabling the drill in the collet to float, relae ke s into entively'to the socket, by an amount equal to the clearance between the collet and the socket, the collet nevertheless being positively driven by the keys 11. The clearance mentioned is not shown, bein very slight, but it may be assumed as being the clearance usually allowed for easy entrance of the collet into the socket, allowmg for little unevenness caused by rough usage and becauseof the accumulation of rust, dirt, etc., on the outside of the collet and the inside of the socket. The engaging end of the collet with the head of the socket may be coned at 21 to still further assist the floating and cen tralizing action of the drill, the end conical formation havingthe effect of automatically centralizing the rear point of the drill which, in conjunction with the usual clearance around the collet, enables the drill to float and aline itself. In place of coning the end of the colletand head of the socket piece,'these engaging parts may be made hemispherical as shown at 22 Fig. 2, or'a hemispherical ended collet may be used in a coned socket as in Fig. 2. The chuck could also with advantage be adapted to turret or capstan lathes for holding the tools in the boxes since it would allow the tools to float. and to automatically aline themselves instead of being rigid as at present,

and a number of operations such as drilling, countersinking, boring, reaming, and facing, could all be performed with the one toolbox such boxes in the ordinar way. Again 1n electric or pneumatic dril in machines, the constant drifting of the dri spindle tends to bend or distort the spindle, whereas by fitting the spindles with chucks in accordance with this invention, drills may be.

changed immediately without stopping the machine and without damage to the spindle.

Claim: a In a tool chuck, in-combination a socket member having a conical inner end portion,

a cylindrical collet engaging the socket, the said collet being of less diameter than the diameter of the socket to provide an annular clearance between the collet and the socket, said collet having an end with a rounded edge adaptcdto engage the conical end of the socket, said collet having recesses,

and said socket having perforations, radially movable keys in the perforations, said keys being adapted to loosely engage the re- J WILLIAM BARNES.

Witnesses:

A. J. DAVIES, B. E. KNIGHT.

of a capstan lathe instead of requiring four 

